A calendar watch date indicator drive mechanism including a rotatably driven cam carried by a shaft slidably disposed in a guide groove, the cam being effective, in combination with a jumper, to cause a delayed, sharp, rotational advance of the date indicator means when sliding movement of the cam is mechanically arrested.
Apparatus for periodically changing calendar information displayed in a timepiece while holding the information-carrying elements motionless between successive changes to insure that the current day and date are properly displayed. A cam mechanism connects the element or elements to the time measuring components of the timepiece so as to allow relative movement therebetween during the interval between successive day and date changes but to impart a quick advancing motion to the elements at the end of the interval to display the next succeeding day and date. A positive drive connection is thus always maintained with the information-carrying elements, notwithstanding that they are moved only intermittently. The cam mechanism also permits turning back of the day element for resetting purposes and provision is made for adjustment of the date element independently of the day element.
A calendar watch movement with a double cam arrangement that drives the date-indicating wheel one step every 24 hours and locks the wheel between driving periods. The first cam has a hook that engages the toothed inner portion of the date-indicating wheel and advances the wheel by one tooth each 24 hours. The cam also has an arcuate peripheral portion that fits in between two successive teeth and locks the wheel when it is not being advanced. The first cam is integral with a co-axial star wheel which is driven by a second cam having both a hook and an adjacent shoulder that advance the star extensions. The second cam is driven by the hour wheel.
In a calendar watch, a day and date drive and dial indicator stepping mechanism including a pair of rotatably driven cams, the cams being geared to revolve at relatively different rates, one of the cams rotating at the rate of one revolution per day and operable to advance a day-indicator dial one step each day, and the second of the cams rotating at a rate of n revolutions per day, n being an integer greater than one, the second cam being rotatable about a shaft slidably engaged in a guide groove, means being provided to shift the second cam for periodic engagement with and to advance a date-indicating calendar ring one step for each n revolutions of the cam, whereby very rapid date and day setting and correction are rendered feasible.
